Certain electronic devices and circuits employ current regulators to provide a relatively constant average current. For example, certain illumination devices provide illumination at an intensity related to the average current through the device. By selectively regulating the average current to different values at different times, an illumination device may be used to provide illumination at selectable intensity levels.
The average current may be changed by controlling the instantaneous current to the load. In certain illumination devices, the emitted color spectrum may be related to the instantaneous current through the device. For example, many light emitting diodes (LEDs) provide light at different wavelengths when driven at differing levels of instantaneous current. In this example, independent control of the average current and the instantaneous current allows for independent control of the emitted color spectrum and the intensity of the illumination.